1. Email Service CPTE 433 John Beckett

2. The Fundamentals Reliable Scalable –Issue is speed Flexible –Clients, locations Growing issue: Spam control Growing issue: Storage

3. Privacy Fit with your organization’s culture. Clearly state policy. Distribute policy; get signatures. Use policy as a statement of maximum intrusion, not minimum. Keep incidentally-acquired knowledge secret.

4. Namespaces See previous chapter. Two issues: –Recognition of who this is –Non-duplication Special problem for colleges: marriage What about when people move around? –You might have an alias list pointing to people with specific responsibilities, e.g. eclasshelp.

5. Reliability Upgrade plans for email must be laid more carefully than those for other services. Better to hold mail at bay than to lose it. –Simplest method: unplug the Ethernet jack or take down the service

6. Aspects Mail Transport –This is done by the equipment designated to the right of the “@”. –In DNS, this is the “MX” record. Delivery –GUI / non-GUI client –Webmail/OWA/SquirrelMail (is both client and server) –Consider protocols used: POP3 and IMAP4 List Processing –Big question is, who can send to which list?

7. Fading Technologies MTA on a client machine –May wish to deny this in your firewall Proprietary protocols –CCMail –CompuServe

8. Emerging Technologies Encryption* Non-repudiation* Spam control * This is a reason SAU has migrated from Procmail to Microsoft Exchange Server.

9. Automation Setting up the account should be part of the process of signing up for a job. List administration should be automated either ex officio or at user’s election. What about when people leave? –No forwarding outside. –Either refuse the mail or send it to their replacement. –At SAU: When does a person really leave?

10. Monitoring Watch disk space consumption. That will tell you: –If someone is being attacked. –If you are not filtering SPAM properly. –If someone is using email to do something that should be done through another process. Watch the bandwidth. –Positive trend: more bandwidth on connection –Negative trend: SPAM

11. Redundancy Keep mail flowing in and out of the site even if one mail exchanger goes down.

12. Scaling Move other services off the mail machine. Separate mail functions such as WebMail client and MTA. Get a bigger machine. Do a better job of SPAM control. Provide alternate means or hosts for troublesome emails –Art department example.

13. Security Your mail system will be a target. If you count SPAM, it’s a target every second of the day! Watch the resources: disk I/O, disk space, bandwidth. Of course, stay updated.

14. Backups Do you want to back up local folders? –Yes: You have to be able to recover it if it breaks. –Yes: You may be required to recover deleted emails. –No: That’s not your job. –No: Leaves unnecessary records that could be used by a prosecutorial opponent. Backup policy should be clearly stated and understood by all.

15. High-Volume Lists You may want to split the list into multiple sub-lists for simultaneous processing. GC example: From 4 hours to 30 minutes on a 30,000-person list.

16. Consider Off-Site Gmail.com is happy to do it (free!)